Allow non-registry dependencies in `uv pip list --outdated` (#8939)

## Summary

Closes https://github.com/astral-sh/uv/issues/8926.

crates/uv/src/commands/pip/latest.rs

@@ -27,12 +27,20 @@ impl<'env> LatestClient<'env> {
         package: &PackageName,
         index: Option<&IndexUrl>,
     ) -> anyhow::Result<Option<DistFilename>, uv_client::Error> {
+        let archives = match self.client.simple(package, index, self.capabilities).await {
+            Ok(archives) => archives,
+            Err(err) => {
+                return match err.into_kind() {
+                    uv_client::ErrorKind::PackageNotFound(_) => Ok(None),
+                    uv_client::ErrorKind::NoIndex(_) => Ok(None),
+                    uv_client::ErrorKind::Offline(_) => Ok(None),
+                    kind => Err(kind.into()),
+                }
+            }
+        };
+
         let mut latest: Option<DistFilename> = None;
-        for (_, archive) in self
-            .client
-            .simple(package, index, self.capabilities)
-            .await?
-        {
+        for (_, archive) in archives {
             for datum in archive.iter().rev() {
                 // Find the first compatible distribution.
                 let files = rkyv::deserialize::<VersionFiles, rkyv::rancor::Error>(&datum.files)

crates/uv/tests/it/pip_list.rs

@@ -189,6 +189,48 @@ fn list_outdated_freeze() {
     );
 }
 
+#[test]
+fn list_outdated_git() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let requirements_txt = context.temp_dir.child("requirements.txt");
+    requirements_txt.write_str(indoc::indoc! {r"
+        iniconfig==1.0.0
+        uv-public-pypackage @ git+https://github.com/astral-test/uv-public-pypackage@0.0.1
+    "})?;
+
+    uv_snapshot!(context.pip_install()
+        .arg("-r")
+        .arg("requirements.txt")
+        .arg("--strict"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 2 packages in [TIME]
+    Prepared 2 packages in [TIME]
+    Installed 2 packages in [TIME]
+     + iniconfig==1.0.0
+     + uv-public-pypackage==0.1.0 (from git+https://github.com/astral-test/uv-public-pypackage@0dacfd662c64cb4ceb16e6cf65a157a8b715b979)
+    "###
+    );
+
+    uv_snapshot!(context.pip_list().arg("--outdated"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    Package   Version Latest Type
+    --------- ------- ------ -----
+    iniconfig 1.0.0   2.0.0  wheel
+
+    ----- stderr -----
+    "###
+    );
+
+    Ok(())
+}
+
 #[test]
 fn list_editable() {
     let context = TestContext::new("3.12");